A common problem in multi-storey construction sites is the safe passage of workers between floors where a set of stairs is not yet installed. A ladder is most commonly preferred for this purpose despite the risks inherent with the ladder shifting under the weight of the worker during use.
Typically during use, erected ladders have a tendency for the ladder heel to slide across a floor so that the ladder inclination diminishes, the ladder thereby loosing contact with the elevated floor. One attempt at redressing this problem has been the use of rubber-covered heels or shoes on the ladder to grip the floor. However, the effectiveness of the rubber-covered heels or shoes is significantly diminished where the floor is covered in loose particles, such as sawdust, which may enable the ladder feet to slide across the floor.
Another problem arises where the ladder is placed on uneven ground such that one heel or shoe of one leg of the ladder may swing freely, thus causing the ladder to rotate unpredictably under a worker's weight. Alternatively, the upper end of the ladder, which rests against an upper floor of the building under construction, may slide laterally, thus resulting in either the ladder toppling over or the weight of the ladder and worker being unevenly distributed between the heels of the ladder. In the latter case, the ladder may freely and unpredictably rotate as it is not optimally stabilised.
A less common, but ever present, risk is where a worker on the ladder overbalances beyond vertical such that the ladder falls directly away from the elevated floor. Usually this is the result of a ladder shifting, for instance, due to the heels slipping or the ladder being placed on uneven ground.
The object of the invention is, therefore, to improve the stability of a ladder bridging vertically spaced sites, in a construction site.